U.S. patent number 11,125,242 [Application Number 14/603,794] was granted by the patent office on 2021-09-21 for compressor system and method of controlling the same.
This patent grant is currently assigned to HANWHA POWER SYSTEMS CO., LTD. The grantee listed for this patent is HANWHA POWER SYSTEMS CO., LTD.. Invention is credited to Joosang Eom, Sungsoon Park.
United States Patent |
11,125,242 |
Park , et al. |
September 21, 2021 |
Compressor system and method of controlling the same
Abstract
Provided is a compressor system including a first compressor
having: an inlet at which a first inlet guide vane is provided; and
an outlet pressure sensor unit configured to measure a pressure at
an outlet of the first compressor; a second compressor including an
inlet at which a second inlet guide vane is provided; a first
control unit configured to adjust a degree of opening of the first
inlet guide vane based on the pressure measured by the outlet
pressure sensor unit, configured to set the outlet pressure of the
first compressor as a set pressure, and configured to generate a
first signal including information about the degree of opening of
the first inlet guide vane; and a second control unit configured to
receive the first signal, and configured to adjust a degree of
opening of the second inlet guide vane to control an amount of
fluid flowing into the second compressor.
Inventors: |
Park; Sungsoon (Changwon-si,
KR), Eom; Joosang (Changwon-si, KR) |
Applicant: |
Name |
City |
State |
Country |
Type |
HANWHA POWER SYSTEMS CO., LTD. |
Changwon-si |
N/A |
KR |
|
|
Assignee: |
HANWHA POWER SYSTEMS CO., LTD
(Changwon-si, KR)
|
Family
ID: |
53678611 |
Appl.
No.: |
14/603,794 |
Filed: |
January 23, 2015 |
Prior Publication Data
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|
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Document
Identifier |
Publication Date |
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US 20150211518 A1 |
Jul 30, 2015 |
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Foreign Application Priority Data
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Jan 24, 2014 [KR] |
|
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10-2014-0009171 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F04D
27/0246 (20130101); F04D 27/0269 (20130101) |
Current International
Class: |
F04C
28/02 (20060101); F04C 18/08 (20060101); F04C
23/00 (20060101); F04C 28/24 (20060101); F04D
27/02 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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101739686 |
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Jun 2010 |
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CN |
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2006-63813 |
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Mar 2006 |
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JP |
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Other References
Mei Xiao et al., "Background Subtraction Algorithm Based on Online
Clustering", Pattern Recognition and Artificial Intelligence, vol.
20, No. 1, Feb. 28, 2007. pp. 35-41. cited by applicant .
Communication dated Jun. 5, 2018, issued by the State Intellectual
Property Office of P.R. China in counterpart Chinese application
No. 201410425393.0. cited by applicant .
Communication dated Jan. 28, 2020, issued by the Korean
Intellectual Property Office in counterpart Korean Application No.
10-2014-0009171. cited by applicant.
|
Primary Examiner: Plakkoottam; Dominick L
Assistant Examiner: Nichols; Charles W
Attorney, Agent or Firm: Sughrue Mion, PLLC
Claims
What is claimed is:
1. A compressor system comprising: a first compressor comprising:
an inlet at which a first inlet guide vane is provided; and an
outlet pressure sensor unit configured to measure a pressure at an
outlet of the first compressor; a second compressor comprising an
inlet at which a second inlet guide vane is provided; a third
compressor comprising an inlet at which a third inlet guide vane is
provided; a first control unit configured to adjust a degree of
opening of the first inlet guide vane based on the pressure
measured by the outlet pressure sensor unit, configured to compare
the outlet pressure of the first compressor with a set pressure to
set the outlet pressure of the first compressor as the set
pressure, and configured to generate a first signal including
information about the degree of opening of the first inlet guide
vane, the set pressure being less than the maximum operational
pressure of the first compressor; a second control unit configured
to receive the first signal, and configured to send a second
signal, corresponding to the first signal, to the second inlet
guide vane and the third inlet guide vane so as to adjust a degree
of opening of the second inlet guide vane to control an amount of
fluid flowing into the second compressor and to adjust a degree of
opening of the third inlet guide vane to control an amount of fluid
flowing into the third compressor, respectively; a first anti-surge
valve unit connected to the first compressor and configured to
adjust a point in time of surging of the first compressor or
configured to reduce a number of occurrences of surging of the
first compressor; and a second anti-surge valve unit connected to
the second compressor and configured to adjust a point in time of
surging of the second compressor or configured to reduce a number
of occurrences of surging of the second compressor, a third
anti-surge valve unit connected to the third compressor and
configured to adjust a point in time of surging of the third
compressor or configured to reduce a number of occurrences of
surging of the third compressor, wherein the second control unit is
configured to adjust the degree of opening of the second inlet
guide vane after the first control unit adjusts the degree of
opening of the first inlet guide vane to set the outlet pressure of
the first compressor as the set pressure, wherein based on the
pressure measured by the outlet pressure sensor unit, the first,
second, and third inlet guide vanes and the first, second, and
third anti-surge valve units are controlled, wherein the degree of
opening of the first inlet guide vane, the degree of opening of the
second inlet guide vane, and the degree of opening of the third
inlet guide vane are controlled to be equal, and wherein, based on
the outlet pressure of the first compressor, an opening degree of
the first anti-surge valve unit, an opening degree of the second
anti-surge valve unit, and an opening degree of the third
anti-surge valve unit are controlled to be equal.
2. The compressor system of claim 1, wherein the first control unit
and the second control unit control the first inlet guide vane and
the second inlet guide vane respectively so that the pressure at
the outlet of the first compressor and a pressure at the outlet of
the second compressor are equal.
3. The compressor system of claim 1, further comprising a filter
unit configured to receive the first signal from the first control
unit, configured to remove noise from the first signal, and
configured to transfer the first signal to the second control
unit.
4. The compressor system of claim 1, wherein the second compressor
and the third compressor are connected in parallel with the first
compressor.
5. The compressor system of claim 1 further comprising: a first
guide flow path connected to the outlet of the first compressor and
configured to guide the fluid compressed by the first compressor to
an exterior of the compressor system; a second guide flow path
connected to the outlet of the second compressor and configured to
the fluid compressed by the second compressor to the exterior of
the compressor system; a third guide flow path connected to the
first guide flow path and the second guide flow path and configured
to guide the fluid to the exterior of the compressor system; a vent
flow path branched off from at least one selected from a group
consisting of the first guide flow path and the second guide flow
path and configured to guide the fluid to the outside; and a surge
valve unit provided on the vent flow path and configured to
selectively open and close the vent flow path.
6. The compressor system of claim 1, wherein the second compressor
is provided in parallel with the first compressor.
7. A method of controlling a compressor system, the method
comprising: measuring an outlet pressure of a first compressor;
comparing the outlet pressure of the first compressor with a set
pressure, the set pressure being less than the maximum operational
pressure of the first compressor; controlling a degree of opening
of a first inlet guide vane and setting the outlet pressure of the
first compressor as the set pressure; converting information about
the degree of opening of the first inlet guide vane into a first
signal; passing the first signal through a low pass filter,
filtering the first signal to remove noise, and sending the
filtered first signal to a second control unit; sending, with the
second control unit, a second signal corresponding to the first
signal to a second inlet guide vane installed at an inlet of a
second compressor and to a third inlet guide vane installed at an
inlet of a third compressor; setting a degree of opening of the
second inlet guide vane to be equal to the degree of opening of a
first inlet guide after the degree of opening of the first inlet
guide vane is adjusted to be the set pressure; providing a first
anti-surge valve unit connected to the first compressor to adjust a
point in time of surging of the first compressor or to reduce a
number of occurrences of surging of the first compressor; providing
a second anti-surge valve unit connected to the second compressor
to adjust a point in time of surging of the second compressor or to
reduce a number of occurrences of surging of the second compressor;
providing a third anti-surge valve unit connected to the third
compressor and configured to adjust a point in time of surging of
the third compressor or configured to reduce a number of
occurrences of surging of the third compressor; and controlling the
first, second, and third inlet guide vanes and the first, second,
and third anti-surge valve units based on the measured outlet
pressure of the first compressor, wherein the degree of opening of
the second inlet guide vane and a degree of opening of the third
inlet guide vane is following the degree of opening of the first
inlet guide vane to be equal.
8. The method of claim 7 further comprising setting the outlet
pressure of the first compressor and a pressure at an outlet
pressure of the second compressor to be equal.
Description
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority from Korean Patent Application No.
10-2014-0009171, filed on Jan. 24, 2014, in the Korean Intellectual
Property Office, the disclosure of which is incorporated herein by
reference in its entirety.
BACKGROUND
1. Field
Apparatuses and methods consistent with exemplary embodiments
relate to a compressor system and a method of controlling the
same.
2. Description of the Related Art
As core equipment of a power plant, a compressor serves various
functions (i.e., to pressurize and supply measuring gas, process
gas, etc.). A plurality of compressors having the same function may
be arranged and connected in parallel to simultaneously operate,
thereby constituting a system of compressors. When the plurality of
compressors are connected in parallel and operated, the number of
operating compressors may be adjusted according to the amount of
gas consumed in a power plant, and the operating compressors are
controlled to evenly share a load so that the efficiency of a
process and the life span of the plurality of compressors may be
increased as much as possible.
In order to evenly distribute the load amongst the plurality of
compressors, it is possible to increase the set pressure of a
compressor having a lighter load, transfer a same flow amount
command to the remaining compressors of the plurality of
compressors, or uniformly maintain buffering distances between
surge lines and operating points of the plurality of
compressors.
However, according to the above method, the compressor system is
stably operated only when a control gain of a controller is changed
according to a change in the number of compressors connected in the
overall system.
For example, while the system operates stably by using one
compressor, if the load of the system increases and another
compressor is additionally operated, the same effect as if the
control gain had become double that of a normal state is achieved.
Therefore, a transient response characteristic is degraded, and
overshoot occurs, so that the pressure of the system may
continuously fluctuate. On the other hand, if the number of
operating compressors decreases while the system operates stably,
the control gain of the controller also decreases. Therefore, the
speed of achieving a control objective decreases, and a normal
state error may occur. For this reason, when the load distribution
method is used, a function of continuously receiving information
about the number of operating compressors and adjusting the gain
based on the information is additionally necessary.
In addition, according to the above load distribution method, a
command for load equalization is generated when a load difference
between individual compression periods is a specific value or more,
and thus it is difficult for all the compressors to maintain the
same load at all times.
An apparatus and method for controlling the operation of a gas
turbine having general compressors as described above are disclosed
in detail in Korean Patent Publication No. 2010-0043065.
SUMMARY
One or more exemplary embodiments provide a compressor system for
evenly distributing a load by causing inlet guide vanes to have a
same degree of opening, and a method of controlling the compressor
system.
Additional aspects will be set forth in part in the description
which follows and, in part, will be apparent from the description,
or may be learned by practice of the presented exemplary
embodiments.
According to an aspect of an exemplary embodiments, there is
provided a compressor system including: a first compressor having:
an inlet at which a first inlet guide vane is provided; and an
outlet pressure sensor unit configured to measure a pressure at an
outlet of the first compressor; a second compressor including an
inlet at which a second inlet guide vane is provided; a first
control unit configured to adjust a degree of opening of the first
inlet guide vane based on the pressure measured by the outlet
pressure sensor unit, configured to set the outlet pressure of the
first compressor as a set pressure, and configured to generate a
first signal including information about the degree of opening of
the first inlet guide vane; and a second control unit configured to
receive the first signal, and configured to adjust a degree of
opening of the second inlet guide vane to control an amount of
fluid flowing into the second compressor.
The first control unit and the second control unit may control the
first inlet guide vane and the second inlet guide vane respectively
so that the degree of opening of the first inlet guide vane and the
degree of opening of the second inlet guide vane are equal.
The first control unit and the second control unit may control the
first inlet guide vane and the second inlet guide vane respectively
so that the pressure at the outlet of the first compressor and a
pressure at the outlet of the second compressor are equal.
The compressor system may further include a filter unit configured
to receive the first signal from the first control unit, configured
to remove noise from the first signal, and configured to transfer
the first signal to the second control unit.
The second compressor may include a plurality of the second
compressors, and the plurality of second compressors are connected
in parallel with the first compressor.
The compressor system may further include: a first guide flow path
connected to the outlet of the first compressor and configured to
guide the fluid compressed by the first compressor to an exterior
of the compressor system; a second guide flow path connected to the
outlet of the second compressor and configured to the fluid
compressed by the second compressor to the exterior of the
compressor system; a third guide flow path connected to the first
guide flow path and the second guide flow path and configured to
the fluid to the exterior of the compressor system; a vent flow
path branched off from at least one selected from a group
consisting of the first guide flow path and the second guide flow
path and configured to guide the fluid to the outside; and a surge
valve unit provided on the vent flow path and configured to
selectively open and close the vent flow path.
The second compressor may be provided in parallel with the first
compressor.
The compressor system may further include: a first anti-surge valve
unit connected to the first compressor and configured to adjust a
point in time of surging of the first compressor or configured to
reduce a number of occurrences of surging of the first compressor;
and a second anti-surge valve unit connected to the second
compressor and configured to adjust a point in time of surging of
the second compressor or configured to reduce a number of
occurrences of surging of the second compressor
According to an aspect of another exemplary embodiments, there is
provided a method of controlling a compressor system including:
measuring an outlet pressure of a first compressor; comparing the
outlet pressure of the first compressor with a set pressure;
controlling a degree of opening of a first inlet guide vane and
setting the outlet pressure of the first compressor as the set
pressure; converting information about the degree of opening of the
first inlet guide vane into a first signal; passing the first
signal through a low pass filter, filtering the first signal to
remove noise, and sending the filtered first signal to a second
control unit; sending a second signal corresponding to the first
signal to a second inlet guide vane installed at an inlet of a
second compressor; and setting a degree of opening of the second
inlet guide vane to be equal to the degree of opening of a first
inlet guide.
The method may further include setting the outlet pressure of the
first compressor and a pressure at an outlet pressure of the second
compressor to be equal.
The method may further include: providing a first anti-surge valve
unit connected to the first compressor to adjust a point in time of
surging of the first compressor or to reduce a number of
occurrences of surging of the first compressor; and providing a
second anti-surge valve unit connected to the second compressor
unit to adjust a point in time of surging of the second compressor
or to reduce a number of occurrences of surging of the second
compressor.
The setting the degree of opening of the second inlet guide vane
may include setting the degree of opening of the second inlet guide
vane after the setting the outlet pressure of the first compressor
as the set pressure.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and/or other aspects will become apparent and more
readily appreciated from the following description of exemplary
embodiments, taken in conjunction with the accompanying drawings in
which:
FIG. 1 is the conceptual diagram of a compressor system according
to an exemplary embodiment;
FIG. 2 is a block diagram showing a control flow of the compressor
system shown in FIG. 1 according to an exemplary embodiment;
and
FIG. 3 is a flowchart illustrating a control sequence of the
compressor system shown in FIG. 1 according to an exemplary
embodiment.
DETAILED DESCRIPTION
Reference will now be made in detail to exemplary embodiments,
examples of which are illustrated in the accompanying drawings,
wherein like reference numerals refer to like elements throughout.
In this regard, the exemplary embodiments may have different forms
and should not be construed as being limited to the descriptions
set forth herein. Accordingly, the exemplary embodiments are merely
described below, by referring to the figures, to explain aspects of
the present description. The inventive concept is only defined by
the claims. Meanwhile, the terminology used in this application is
used to describe exemplary embodiments and is not intended to limit
the inventive concept. In this application, an expression in the
singular includes an expression in the plural unless otherwise
stated. As used herein, the terms "comprises", "includes", and
"has" and/or "comprising", "including", and "having" indicate the
existence of components, steps, operations, and/or elements
mentioned herein without excluding in advance the possibility of
existence or addition of one or more other components, steps,
operations, and/or elements. The terms "first", "second", etc. can
be used to describe various elements, but these elements are not
limited by the terms. The terms are only used to distinguish one
element from other elements.
FIG. 1 is the conceptual diagram of a compressor system according
to an exemplary embodiment, and FIG. 2 is a block diagram showing a
control flow of the compressor system shown in FIG. 1 according to
an exemplary embodiment.
Referring to FIGS. 1 and 2, a compressor system 100 may include a
lead compressor 110, a first inlet guide vane 113, a first control
unit 120, a filter unit 121, a first anti-surge valve unit 123, a
second control unit 130, a second anti-surge valve unit 131, a lag
compressor 140, a second inlet guide vane 143, a first guide flow
path 151, a first vent flow path 152, a second guide flow path 153,
and a second vent flow path 154.
The lead compressor 110 may set an amount of load to be shared in
order to share the load amount with the lag compressor 140. Also,
the lead compressor 110 may compare a previously set pressure with
a pressure obtained during an actual operation to compare the
previously set load with an actual load. The lead compressor 110 is
connected to a first drive unit 111 through a first rotation axis
112 and receives a turning force from the first drive unit 111. As
the lead compressor 110, any well-known compressor of the related
art may be used, and thus, the structure and the operation
principle of the lead compressor 110 will not be described in
detail herein.
At the inlet of the lead compressor 110, the first inlet guide vane
113 is installed and may control the amount of fluid flowing into
the lead compressor 110. At the outlet of the lead compressor 110,
a first pressure sensor unit 114 is installed and may measure the
pressure of the fluid at the outlet of the lead compressor 110.
The outlet of the lead compressor 110 is connected to the first
guide flow path 151 and may guide the fluid compressed by the lead
compressor 110 to the outside of the compressor system 100. The
first pressure sensor unit 114 is installed on the first guide flow
path 151, and the installation space of the first pressure sensor
unit 114 is reduced as much as possible, so that the first pressure
sensor 114 may be compactly installed within the compressor system
100. Also, the first vent flow path 152 is formed on the first
guide flow path 151, so that the first anti-surge valve unit 123
may be installed.
The first anti-surge valve unit 123 may have a first anti-surge
valve 125 and a first anti-surge valve control unit 124. The first
anti-surge valve 125 may open and close to prevent surging in the
lead compressor 110.
When surging occurs in the lead compressor 110, the first
anti-surge valve unit 123 opens the first anti-surge valve 125 to
adjust a point in time of surging or reduce the number of
occurrences of surging as much as possible. Also, the first
anti-surge valve unit 123 may set a pressure at which the
occurrence of surging is expected, and open the first anti-surge
valve 125 at the set pressure to prevent the occurrence of
surging.
The first anti-surge valve control unit 124 may determine whether
or not surging has occurred in the lead compressor 110 based on a
signal. Also, the first anti-surge valve control unit 124 may send
a signal for opening and closing the first anti-surge valve 125 to
control the first anti-surge valve 125. The anti-surge valve
control unit 124 may be connected to the first control unit 120,
which will be described below, and control the first anti-surge
valve 125 by using the pressure signal of the outlet of the lead
compressor 110 sent from the first pressure sensor unit 114.
Alternatively, the first anti-surge valve control unit 124 may have
a surging-check sensor unit (not shown) to determine whether or not
surging has occurred in the lead compressor, thereby controlling
the first anti-surge valve 125 independently. However, for
convenience of description, the following description will be given
focusing on the case where the first anti-surge valve control unit
124 is connected to the first control unit 120 and controls the
first anti-surge valve 125.
The first control unit 120 may be connected to the first inlet
guide vane 113, the first pressure sensor unit 114, the filter unit
121, and the first anti-surge valve control unit 124 via a control
signal. Here, the first control unit 120 may take various forms,
and may control all components of the compressor system 100 in
addition to the first inlet guide vane 113, the first pressure
sensor unit 114, the filter unit 121, and the first anti-surge
valve control unit 124. In particular, the first control unit 120
may be formed in various manners, such as a portable terminal, a
personal computer (PC), and a laptop computer.
The first pressure sensor unit 114 measures a pressure at the
outlet of the lead compressor 110, and the first control unit 120
may receive a signal indicating the outlet pressure of the lead
compressor 110. The first control unit 120 may compare the received
output pressure with the pressure at the outlet of the lead
compressor 110 set by the user and send a signal for adjusting the
degree of opening of the first inlet guide vane 113 (hereinafter
referred to as an adjustment signal) to the first inlet guide vane
113. Also, the first control unit 120 may send a signal indicating
the degree of opening of the first inlet guide vane 113
(hereinafter referred to as a first signal) to the filter unit
121.
The first control unit 120 may send a signal for controlling the
first anti-surge valve control unit 124 to the first anti-surge
valve control unit 124, so that the first anti-surge valve 125 may
open and reduce the occurrence of surging. Also, the first control
unit 120 may adjust the degree of opening of the first inlet guide
vane 113 to adjust the outlet pressure of the lead compressor 110,
thereby reducing the occurrence of surging.
In order to selectively send the first signal to the second control
unit 130, a low pass filter may be used as the filter unit 121. In
other words, when the first signal has a specific frequency or
less, the first signal passes through the filter unit 121 and
arrives at the second control unit 130. On the other hand, when the
first signal has a higher frequency than the specific frequency,
the first signal is blocked. Therefore, noise resulting from a
drastic change in load is removed, so that the stability of the
system may be ensured.
The second control unit 130 may be connected to the second inlet
guide vane 143, the second anti-surge valve unit 131, and the
filter unit 121 with a control signal. Here, the second control
unit 130 may take various forms, and may control all components of
the compressor system 100 in addition to the second inlet guide
vane 143, the second anti-surge valve unit 131, and the filter unit
121. In particular, such a second control unit 130 may be formed in
various manners, such as a portable terminal, a PC, and a laptop
computer as discussed previously regarding the first control unit
120.
The second control unit 130 receives the first signal from the
filter unit 121. Also the second control unit 130 sends a second
signal corresponding to the first signal to the second inlet guide
vane 143. The second signal causes the degree of opening of the
second inlet guide vane 143 to be the same as the degree of opening
of the first inlet guide vane 113. In other words, by adjusting the
degree of opening of the second inlet guide vane 143, the second
control unit 130 may cause the outlet pressure of the lag
compressor 140 to be the same as the outlet pressure of the lead
compressor 110. When there is a plurality of the lag compressors
140, the second control unit 130 may control the outlet pressures
of the plurality of lag compressors 140 by sending the second
signal to the respective inlet guide vanes 143 of the plurality of
lag compressors 140.
Also, the second control unit 130 may send a signal for controlling
the second anti-surge valve control unit 132 to the second
anti-surge valve control unit 132. At this time, the second control
unit 130 may adjust the degree of opening of the second inlet guide
vane 143 to adjust the outlet pressure of the lag compressor
140.
The second control unit 130 adjusts the degree of opening of the
second inlet guide vane 143 to share a load with the lead
compressor 110. There may be a plurality of the lag compressors
140, and the plurality of lag compressors 140 may be connected in
parallel with the lead compressor 110. The lag compressor 140 is
connected to a second drive unit 141 through a second rotation axis
142 and receives a turning force from the second drive unit 141.
Since the structure and the operation of the lag compressor 140 are
similar to those of the lead compressor 110, their description will
be omitted or only briefly given here.
At the inlet of the lag compressor 140, the second inlet guide vane
143 is installed and may control the amount of fluid flowing into
the lag compressor 110. At the outlet of the lag compressor 140, a
second pressure sensor unit 144 is installed and may measure the
pressure of the fluid at the outlet of the lag compressor 140.
The outlet of the lag compressor 140 is connected to the second
guide flow path 153 and may guide the fluid compressed by the lag
compressor 140 to the outside of the compressor system 100. The
second pressure sensor unit 144 is installed on the first guide
flow path 153, and the installation space of the second pressure
sensor unit 144 is reduced as much as possible, so that the second
pressure sensor 144 may be compactly installed. Also, the second
vent flow path 154 is formed on the second guide flow path 153, so
that the second anti-surge valve unit 131 may be installed.
The first guide flow path 151 and the second guide flow path 153
together constitute a third guide flow path 155 to discharge the
fluid passed through the lead compressor 110 and the lag compressor
140 to the outside. In addition, a third pressure sensor unit 160
is installed on the third guide flow path 155 and may check the
pressure of the compressed fluid.
FIG. 3 is a flowchart illustrating a control sequence of the
compressor system shown in FIG. 1 according to an exemplary
embodiment.
A method of sharing a load between the lead compressor 110 and the
lag compressor (or the plurality of lag compressors)140 will be
described with reference to FIG. 3.
For load sharing, a pressure at each of the outlets of the lead
compressor 110 and the lag compressor 140 is set. More
specifically, pressures of the lead compressor 110 and the lag
compressor may be set so that the fluid has the same pressure at
the respective outlets and the lead compressor 110 and the lag
compressor 140 have the same load. The first pressure sensor unit
114 at the outlet of the lead compressor 110 checks the outlet
pressure of the lead compressor 110 and sends an outlet pressure
signal to the first control unit 120 (operation S110).
The first control unit 120 determines whether or not the outlet
pressure of the lead compressor 110 is the same as the previously
set pressures (operation S120).
When the outlet pressure of the lead compressor 110 differs from
the corresponding set pressure, the degree of opening of the first
inlet guide vane 113 is adjusted so that the outlet pressure of the
lead compressor 110 becomes the same as the corresponding set
pressure. In other words, the first control unit 120 sends an
adjustment signal to the first inlet guide vane 113 and adjusts the
degree of opening of the first inlet guide vane 113 to change the
flow amount of fluid, thereby causing the outlet pressure of the
lead compressor 110 to be the same as the corresponding set
pressure (operation S130).
At this time, the first control unit 120 converts information about
the degree of opening of the first inlet guide vane 113 into a
first signal. The first signal causes the degree of opening of the
second inlet guide vane 143 and the degree of opening of the first
inlet guide vane 113 to be the same so that the lag compressor 140
and the lead compressor 110 evenly share the load (operation
S140).
The first control unit 120 sends the first signal to the filter
unit 121. The filter unit 121 may maintain the stability of the
compressor system 100 by removing noise from the first signal. The
filter unit 121 removes fluctuations of the first signal, and the
first signal is selectively sent, so that the stability of the
system 100 may be improved (operation S150).
The second control unit 130 may receive the first signal passed
through the filter unit 121, generate a second signal corresponding
to the first signal, and send the second signal to the second inlet
guide vane 143. The second signal causes the second inlet guide
vane 143 to have the same degree of opening as the first inlet
guide vane 113 (operation S160).
The second inlet guide vane 143 having received the second signal
has the same degree of opening as the first inlet guide vane 113.
When the degree of opening of the first inlet guide vane 113 and
the degree of opening of the second inlet guide vane 143 are
identical, the amount of the fluid flowing into the lead compressor
110 and the amount of the fluid flowing into the lag compressor 140
are identical, and the outlet pressures of the respective
compressors become identical. In other words, the pressure of the
fluid measured by the first pressure sensor unit 114 and the
pressure of the fluid measured by the second pressure sensor unit
144 may become identical (operation S170).
In the compressor system 100, the inlet guide vane of the lead
compressor 110 and the inlet guide vane of the lag compressor 140
are controlled to have the same degree of opening, and a load is
evenly distributed, so that the stability of the system 100 may be
ensured. In other words, the respective compressors are controlled
to have the same output pressure, and the load of the compressor
system 100 is evenly distributed, that is, the load is not
concentrated on a specific compressor, so that the compressor
system 100 may stably operate.
In addition, in the compressor system 100, a control signal may
pass through the filter unit 121 so that noise may be removed.
Therefore, it is possible to prevent excessive changes in pressure
and load that may be caused when a plurality of inlet guide vanes
simultaneously operate, so that the stability of the system 100 may
be ensured.
Further, in the compressor system 100, even when communication is
cut off from the outside, the degree of opening of the inlet guide
vane of each compressor is maintained as it is, and no drastic
change in process is caused. Also, regardless of a change in the
number of operating compressors, it is possible to exhibit control
performance at the same level as input control of the lead
compressor 110. Consequently, high reliability may be ensured.
Moreover, in the compressor system 100, an anti-surge valve unit is
prepared for each compressor, and it is possible to perform a surge
prevention operation and immediately perform a surge avoidance
operation upon the occurrence of surging.
As described above, according to the one or more of the above
exemplary embodiments, the inlet guide vanes of a lead compressor
and a lag compressor have the same degree of opening to evenly
distribute a load, so that the stability of a compressor system may
be ensured.
In addition, a filter unit is prepared to prevent excessive changes
in pressure and load, so that the compressor system may be stably
operated. The scope of the inventive concept is not limited to
these effects.
It should be understood that the exemplary embodiments described
herein should be considered in a descriptive sense only and not for
purposes of limitation. Descriptions of features or aspects within
each exemplary embodiment should typically be considered as
available for other similar features or aspects in other exemplary
embodiments.
While exemplary embodiments have been described with above, it will
be understood by those of ordinary skill in the art that various
changes in form and details may be made therein without departing
from the spirit and scope of the inventive concept as defined by
the following claims.
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